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Sulfur(II)—metal coordination compounds. Group VI metal carbonyl complexes with N,N′-thiobisamines ligands
Inorganica Chimica Acta, 85 (1984) 61-64
61
Sulfur(II)-Metal Coordination Compounds. Group VI Metal Carbonyl Complexes with N,N’-Thiobisamines Ligands CARLOS DIAZ and GUILLERMO GONZALEZ*+ Department
of Chemistry, Faculty of Basic and Pharmaceutical Sciences, University of
Chile,LasPalmeras3425 Santiago,Chile
Received August 25, 1983
The novel complexes M(CO),S(NR,), (M = Cr, MO or W) have been prepared by the addition of N,N’-thiobisamine (NR, = dimethylamine, piperidine, morpholine or dibenzylamine) to UV-irradiated tetrahydrojiuan solutions of M(CO)6. The IR, ‘HNMR, and UV-visible spectral data used for characterizing the products support the coordination of the thiobisamine via the sulfur(H) atom.
Introduction N,N’-thiobisamines are known to be stable and unreactive species that can be crystallized from water or alcohols only undergoing hydrolysis or alcoholysis reactions in the presence of acids [l-3]. In spite of the nucleophilic characteristics expected from the lone pairs on sulfur and nitrogen atoms, only a reduced number of often unstable adducts with boron(III) compounds, BX, (X = H, F or C6H,) have been reported [l-4]. Attempts to prepare complexes with Cu(II), Cu(1) and Ag(1) ions have failed; thiobisamines are unreactive towards these metal ions under anhydrous conditions, undergoing hydrolysis followed by redox processes in the presence of water [2]. The low nucleophilicity of such compounds can be attributed to the nature of the S-N linkage that, according to spectral as well as X-ray structural determinations [S-7], has some double bond character. Nevertheless, by considering that in the sulfur atom besides the lone electron pairs there are also d orbitals that could be able to act as n-acceptor, we have undertaken the coordination of thiobisamine to metals in a rather low oxidation state. In this work we describe the synthesis of novel carbonyl complexes of thiobisamines with metal carbonyls of the group VI.
Experimental N,N’-thiobisamines were prepared according to literature procedures [8]. Commercially available metal carbonyls (Merck) were used without further purification. Tetrahydrofuran (THF) was dried with sodium. All reactions were performed under an oxygen-free nitrogen atmosphere. IR, ‘H-NMR and UVvisible spectral data were obtained by using the Perkin Elmer model 62 1, Varian T-60, and Cary 17 spectrometers respectively. The general procedure for the synthesis of the thiobisamine metalcarbonyl complexes: a solution of 3.5 mm01 M(C0)6 in ca. 60 ml THF was irradiated (UV Lamp Hanovia, medium pressure 150 w) for 90 min. (for Mo(C06, 120 min.) at room temperature. A solution of 3 mmol of thiobisamine in ca. 20 ml THF was then added and the mixture stirred for 60 min. After removing the solvent under reduced pressure, the excess of hexacarbonyl was sublimed from the residue under vacuum at room temperature. The solid was then redissolved in a n-hexane-n-pentane mixture (for la, pure n-pentane), filtered through kieselguhr, and recovered by evaporating the solvent. Numerous attempts to crystallize such products have failed. Molecular weights (cryoscopic measurements in bencene): la: 377 (talc. 396); 3a: 500 (talc. 528). Analytical data, yields and melting points for the products are shown in Table I.
Results and Discussion The addition of the thiobisamine to a tetrahydrofuran (THF) solution of M(C0)5 (THF) photochemically generated [9, lo] gives rise to the formation of thiobisamine carbonyl complexes according to following chemical equations:
,NR, *Author to whom correspondence should be addressed. TAlexander von Humboldt fellow 1983.
0020-1693/84/$3.00
(CO),M(THF)
+ S,
THF
(CO),MS, NR2 25 =”
0 Elsevier Sequoia/Printed
,W
+ THF NR2 in Switzerland
C. Diaz and G.
62
Nr.
M
NR,
la lb lc Id 2a 3a
Cr
dimethylamine piperidine morpholine dibenzylamine morpholine morpholine
MO W
The products are yellow solids unstable to moisture. Elemental analysis and cryoscopical molecular weight determinations indicate that the products are monosubstituted and monomeric. The molybdenum complex 2a is relatively unstable and was always found to be contamined with free amine. Because of the poor yield reached in the synthesis of la, this compound was identified only by spectral methods. A casual presence of water gives rise, specially for the morpholine derivatives Ic and 3a, to the amine complexes M(CO)sHNR,. Under our conditions, no formation of disubstituted compounds was observed. A vibrational study of the compounds was only achieved by analysing the IR spectra; decomposition TABLE
I. Analytical
Compound
Data, Yield and Melting Point of M(CO)sS(NRz)z
Analysis
(%): Found
C _
laa lb lc Id 2a 3a
46.13(45.91) 40.58(39.36) 64.23(64.28) 36.72(35.43) 29.43(29.53)
aPoor yield, only spectral TABLE
No.
II. IR Spectra
M
Complexes.
Yield (%)
M.P. (“c)
8 30 40 30 35 42
70-71 61-62 79-80 90 (dec) 80 (dec) 93-95
S
N
_
-
_
5.68(5.1) 4.81(4.04) 5.27(4.54) 4.60(3.63) 3.47(3.03)
7.67(7.14) 7.50(7.07) 4.88(4.54) 7.49(6.35) 5.26(5.30)
8.64(8.16) 7.45(8.07) 5.20(5.19) 8.20(7.26) 6.65(6.06
analysis.
of M(CO)sS(NR&
NR,
of the samples by the laser irradiation (CR-4 Argonion laser, line 4880 A) prevented the recording of the Raman spectra. In Table II are reported the frequency values assigned to the vibrations v(CO), u(MC), and 6(MCO). The frequency and the relative intensities of the bands corresponding to stretching vibrations of the CO group indicate, as expected for M(CO)5L structures, a symmetry fundamentally CJv [ll]. Nevertheless, some deviations from this symmetry are suggested by the splitting of the E band as well as by the activity of the Br band in the infrared [ 111. The IR spectra of the thiobisamines coordinated to the metal carbonyls show patterns that are similar to those of the free thiobisamines [6], pointing to a nearly symmetrical metal-thiobisamine interaction. Nevertheless, the frequencies assigned to v(SN),, in the free ligand [6] are shifted to lower values in the complex, as can be observed in data shown in Table III. ‘H NMR and UV-visible spectra of the compounds are also compatible with a symmetrical interaction, indicating that the coordination occurs though the sulfur atom of the thiobisamine. Thus, the ‘H NMR
(Calculated) H
Gonzalez
Complexes
(cm-l)a.
vMCC
vcob
S MCOC
Al(*)
B1
E
A1 (0
Al
E
E
Al
N(CH&
2063~
1988~
1954,1943vs
1932m
550w
443m
658s
630m
lb
N 3
2065~
1989~
1951,194ovs
1929m
560m
443m
660s,sh
646s,sh
lc
N 3,
2069~
1989~
1952,1946vs
1935m
552~
488m
668s
645~s
Id
N(CH&H&
2069~
1990w
1952,1948vs
1936m
554w
445s
662s
643~s
Ns
2079~
1989~
1958,195Ovs
1940m
390w
350s
540m
600s
2078~
1985~
1950,1945vs
1932m
440w
365s
600s
580~
la
Cr
2a
MO
3a
W
Ns
aThe.assignments were made according to references [ 111, [ 141 and Abbreviations: s: strong, m: medium, w: weak, v: very, sh: shoulder.
[ 221.
bn-hexane
solution.
CKBr, solid.
M(CO)$i(NRz)2
63
with N,N’-Thiobisamine
TABLE III. Selected Spectral Data for M(CO)sS(NR& No.
la
M
Cr
lb IC
NRz
2a
MO
3a
W
u(S-N),~
%rlaK (Log)b
6 ‘HNMRC
Free
Complex
N(CHs)z
945s
928s
392
2.98d
N 3
937s,915s
923s,sh;906s
392(3.22)
3.23((CH2)2)e,l.53((CH2)3)e
95Os,922s
930s,sh;920s
393(3.19)
3.53(OCH2)e,3.30(NCH2)e
N(CHzCaHs)z
940m
922m
395(3.4)
7.13(CeH,)d,4.13(CHz)d
Nz
95Os,922s
938s,sh;921s
398
3.50(OCH2)e,3.18(NCH2)e
95Os,922s
933s,918s
370(3.23)
3.56(OCH2)e,3.30(NCH2)e
Nb
Id
Complexes.
‘KBr, solid in cm-l. bn-hexane. Cppm from TMS in CCl4. Abbreviations: s: strong, m: medium, sh: shoulder.
of the complexes (Table III column 3) are similar to those of the free ligands but shifted downfield. For N-coordination two sets of signals, as those reported for the adducts with BH3 [4], should be expected. On the other hand the absorption maxima in UV-visible spectra (Table III column 2) observed at about 390 m~.1 for chromium and molybdenum, and at 370 ml.c for tungsten compounds, can be ascribed to the transition ‘A1 + ‘E that has been considered as characteristic for sulfur coordination in pentacarbonyl chromium and tungsten [ 121 compounds. In Table IV are reported the force constants kr and k2 for the C-O bonds calculated, according to the method of Cotton and Kreihanzel [ 111, from the stretching frequencies of the CO group reported in Table I. The k values obtained for the CO bonds in the thiobisamine complexes agree well with those reported for the same bonds in some Cr(CO)sL complexes in which L was a sulfur ligand [ 13-151. This fact is particularly significant in the case of kr which is very sensitive to the nature of the donor atom, specially to its capacity as a n-acceptor [ 131. The corresponding Graham 6 and rr parameters [ 161 are also reported in Table IV. According to the effects of the thiobisamine coordination on the CO bonds appearing from these data, the N,N’-thiobisamine are weak R-acceptor ligands. However, this is the kind of interaction that permits the formation of the complex in spite of the low nucleophilicity of the sulfur atom in the ligands. Among the complexes M(CO)sL (M = Cr, MO or W) with sulfur ligands reported at the time-with L= thioethers [ 171, thioamides and thioureas [ 18, 191, S(MR3)2 (M = Ge, Sn or Pb) [20], and SPRs [2 l] the thiobisamine complexes described here are the spectra
first metal-sulfur complexes with sulfur in a formal oxidation state +2. The main effects of the coordination to metal carbonyls on the properties of thiobisamine are a higher sensibility to electromagnetical radiation (Raman laser) and a greater susceptibility to hydrolysis. This latter effect is similar to that caused by the presence of acids or by the electrochemical oxidation of the thiobisamine to (R2N)sSt radicals [3], that also activate the heterolysis of the S-N bond.
Acknowledgements The authors thank Prof. E. Fluck, University of Stuttgart and Gmelin Institut Frankfurt, for facilities for performing a part of this work.
References 1 __O.E. Thompson, Q. Rep. Sulp. Chem., 5, 245 (1970). 2 G. Gonzilez, C. Diaz and S. Copaja, Monatsh. Chem., 114, 177 (1983). 3 G. Gonzkz, M. A. Santa Ana and I. Chadwick, J. Chem. Sot. Trans. Farad. II, in press. 4 H. Noth, G. Mikulascheck and W. Rambeck, Z. Anorg. Allg. Chem., 344, 316 (1966). 5 C. Romming, G. 0. Nevstad, J. Songstad, Acta Chem. Stand. A., 36, 399 (1982). 6 C. Diaz, E. Clavijo and G. Gonzilez,
Spectrochim.
Acta,
in press. 7 V. W. Hu, J. W. Gilje and T. T. Bopp, Inorg. Chem., 12, 955 (1973). 8 E. S. Blake,J. Am. Chem. Sot., 6.5, 1267 (1943). 9 M. Baudler and H. Mozaffar-Zanganeh, 2. Anorg. Chem., 423,203 (1976).
AZZg.
64 TABLE
C. Diaz and G. Gonzalez IV. Force Constantsa
Mo(CO)s
s
N (“) P
and Graham
2
WCO)s
aCalculated CReference
according
[ 131.
to the method dReference [ 141.
Parametersb
for C-O
Bonds in M(C0)sS(NR2)2
and other M(CO)sL
Complexes.
kl (md/A)
kz (md/A)
6
n
15.32
15.95
-0.12
0.05
15.29
15.97
0.19
0.01
15.31
15.97
0.10
0.09
15.36 15.44e 15.3oc 15.43e
15.99 15.9oe 15.91c 15.92’
0.13 -0.17 -0.01 -0.12
0.08 0.29 0.14 0.26
15.40
15.97
0.10
0.19
15.35e 15.41e 15.29= 15.38C
15.94e 15.99c 15.99e 15.88c
15.32
15.91
15.29d 15.37d 15.40c 15.28c 15.39c
15.86d 15.96d 15.89c 15.9oe 15.88C
of Cotton and Kreihanzel, eReference [ 161.
10 W. Strohmeier, Angew. Chem. Ed. Engl., 3, 730 (1964). 11 F. A. Cotton and C. S. Kraihanzel, J. Am. Chem. Sot., 84,4432 (1962). 12 E. W. Ainscough, F. J. Birch and A. M. Brodie, Inorg. Chim. Acta, 20, 187 (1976). 13 W. A. Schenk and M. Schmidt, 2. Anorg. Al/g. Chem., 416, 311 (1975). 14 R. A. Brown and G. R. Dobson, Inorg. Chim. Acta, 6, 65 (1972). 15 J. A. Connor and G. A. Hudson, J. Chem. Sot. Dalton 1025 (1975). 16 W. A. Graham, Znorg. Chem., 7, 315 (1968).
reference
-0.05e -0.1 0.02 -0.29
[ 111.
bCalculated
0.15e 0.22 0.10 0.30
0.16
0.02
0.01 0.13 -0.04 0.10 -0.05
0.12 0.10 0.20 0.07 0.20
according
to reference
[ 16 1.
17 H. Schumann, 0. Stelzer, R. Weis, R. Mohtachemi and R. Fischer, Chem. Ber., 106,48 (1973). 18 G. Gonzilez and J. Granifo, Znorg. Chim. Acta, 3.5, 209 (1979). 19 J. Granifo, J. Costamagna, A. Garrao and M. Pieber, J. Inorg. Nucl. Chem., 42, 1587 (1980). 20 W. Ehrl and H. Vahrenkamp, Chem. Ber., 103, 3563 (1970). 21 E. W. Ainscough, A. M. Brodie and A. R. Furness, J. Chem. Sot. Dalton, 2360 (1973). 22 C. Jeanne, R. Pince and R. Poilblanc, Spectrochim. Acta, 3IA, 819 (1975).
61
Sulfur(II)-Metal Coordination Compounds. Group VI Metal Carbonyl Complexes with N,N’-Thiobisamines Ligands CARLOS DIAZ and GUILLERMO GONZALEZ*+ Department
of Chemistry, Faculty of Basic and Pharmaceutical Sciences, University of
Chile,LasPalmeras3425 Santiago,Chile
Received August 25, 1983
The novel complexes M(CO),S(NR,), (M = Cr, MO or W) have been prepared by the addition of N,N’-thiobisamine (NR, = dimethylamine, piperidine, morpholine or dibenzylamine) to UV-irradiated tetrahydrojiuan solutions of M(CO)6. The IR, ‘HNMR, and UV-visible spectral data used for characterizing the products support the coordination of the thiobisamine via the sulfur(H) atom.
Introduction N,N’-thiobisamines are known to be stable and unreactive species that can be crystallized from water or alcohols only undergoing hydrolysis or alcoholysis reactions in the presence of acids [l-3]. In spite of the nucleophilic characteristics expected from the lone pairs on sulfur and nitrogen atoms, only a reduced number of often unstable adducts with boron(III) compounds, BX, (X = H, F or C6H,) have been reported [l-4]. Attempts to prepare complexes with Cu(II), Cu(1) and Ag(1) ions have failed; thiobisamines are unreactive towards these metal ions under anhydrous conditions, undergoing hydrolysis followed by redox processes in the presence of water [2]. The low nucleophilicity of such compounds can be attributed to the nature of the S-N linkage that, according to spectral as well as X-ray structural determinations [S-7], has some double bond character. Nevertheless, by considering that in the sulfur atom besides the lone electron pairs there are also d orbitals that could be able to act as n-acceptor, we have undertaken the coordination of thiobisamine to metals in a rather low oxidation state. In this work we describe the synthesis of novel carbonyl complexes of thiobisamines with metal carbonyls of the group VI.
Experimental N,N’-thiobisamines were prepared according to literature procedures [8]. Commercially available metal carbonyls (Merck) were used without further purification. Tetrahydrofuran (THF) was dried with sodium. All reactions were performed under an oxygen-free nitrogen atmosphere. IR, ‘H-NMR and UVvisible spectral data were obtained by using the Perkin Elmer model 62 1, Varian T-60, and Cary 17 spectrometers respectively. The general procedure for the synthesis of the thiobisamine metalcarbonyl complexes: a solution of 3.5 mm01 M(C0)6 in ca. 60 ml THF was irradiated (UV Lamp Hanovia, medium pressure 150 w) for 90 min. (for Mo(C06, 120 min.) at room temperature. A solution of 3 mmol of thiobisamine in ca. 20 ml THF was then added and the mixture stirred for 60 min. After removing the solvent under reduced pressure, the excess of hexacarbonyl was sublimed from the residue under vacuum at room temperature. The solid was then redissolved in a n-hexane-n-pentane mixture (for la, pure n-pentane), filtered through kieselguhr, and recovered by evaporating the solvent. Numerous attempts to crystallize such products have failed. Molecular weights (cryoscopic measurements in bencene): la: 377 (talc. 396); 3a: 500 (talc. 528). Analytical data, yields and melting points for the products are shown in Table I.
Results and Discussion The addition of the thiobisamine to a tetrahydrofuran (THF) solution of M(C0)5 (THF) photochemically generated [9, lo] gives rise to the formation of thiobisamine carbonyl complexes according to following chemical equations:
,NR, *Author to whom correspondence should be addressed. TAlexander von Humboldt fellow 1983.
0020-1693/84/$3.00
(CO),M(THF)
+ S,
THF
(CO),MS, NR2 25 =”
0 Elsevier Sequoia/Printed
,W
+ THF NR2 in Switzerland
C. Diaz and G.
62
Nr.
M
NR,
la lb lc Id 2a 3a
Cr
dimethylamine piperidine morpholine dibenzylamine morpholine morpholine
MO W
The products are yellow solids unstable to moisture. Elemental analysis and cryoscopical molecular weight determinations indicate that the products are monosubstituted and monomeric. The molybdenum complex 2a is relatively unstable and was always found to be contamined with free amine. Because of the poor yield reached in the synthesis of la, this compound was identified only by spectral methods. A casual presence of water gives rise, specially for the morpholine derivatives Ic and 3a, to the amine complexes M(CO)sHNR,. Under our conditions, no formation of disubstituted compounds was observed. A vibrational study of the compounds was only achieved by analysing the IR spectra; decomposition TABLE
I. Analytical
Compound
Data, Yield and Melting Point of M(CO)sS(NRz)z
Analysis
(%): Found
C _
laa lb lc Id 2a 3a
46.13(45.91) 40.58(39.36) 64.23(64.28) 36.72(35.43) 29.43(29.53)
aPoor yield, only spectral TABLE
No.
II. IR Spectra
M
Complexes.
Yield (%)
M.P. (“c)
8 30 40 30 35 42
70-71 61-62 79-80 90 (dec) 80 (dec) 93-95
S
N
_
-
_
5.68(5.1) 4.81(4.04) 5.27(4.54) 4.60(3.63) 3.47(3.03)
7.67(7.14) 7.50(7.07) 4.88(4.54) 7.49(6.35) 5.26(5.30)
8.64(8.16) 7.45(8.07) 5.20(5.19) 8.20(7.26) 6.65(6.06
analysis.
of M(CO)sS(NR&
NR,
of the samples by the laser irradiation (CR-4 Argonion laser, line 4880 A) prevented the recording of the Raman spectra. In Table II are reported the frequency values assigned to the vibrations v(CO), u(MC), and 6(MCO). The frequency and the relative intensities of the bands corresponding to stretching vibrations of the CO group indicate, as expected for M(CO)5L structures, a symmetry fundamentally CJv [ll]. Nevertheless, some deviations from this symmetry are suggested by the splitting of the E band as well as by the activity of the Br band in the infrared [ 111. The IR spectra of the thiobisamines coordinated to the metal carbonyls show patterns that are similar to those of the free thiobisamines [6], pointing to a nearly symmetrical metal-thiobisamine interaction. Nevertheless, the frequencies assigned to v(SN),, in the free ligand [6] are shifted to lower values in the complex, as can be observed in data shown in Table III. ‘H NMR and UV-visible spectra of the compounds are also compatible with a symmetrical interaction, indicating that the coordination occurs though the sulfur atom of the thiobisamine. Thus, the ‘H NMR
(Calculated) H
Gonzalez
Complexes
(cm-l)a.
vMCC
vcob
S MCOC
Al(*)
B1
E
A1 (0
Al
E
E
Al
N(CH&
2063~
1988~
1954,1943vs
1932m
550w
443m
658s
630m
lb
N 3
2065~
1989~
1951,194ovs
1929m
560m
443m
660s,sh
646s,sh
lc
N 3,
2069~
1989~
1952,1946vs
1935m
552~
488m
668s
645~s
Id
N(CH&H&
2069~
1990w
1952,1948vs
1936m
554w
445s
662s
643~s
Ns
2079~
1989~
1958,195Ovs
1940m
390w
350s
540m
600s
2078~
1985~
1950,1945vs
1932m
440w
365s
600s
580~
la
Cr
2a
MO
3a
W
Ns
aThe.assignments were made according to references [ 111, [ 141 and Abbreviations: s: strong, m: medium, w: weak, v: very, sh: shoulder.
[ 221.
bn-hexane
solution.
CKBr, solid.
M(CO)$i(NRz)2
63
with N,N’-Thiobisamine
TABLE III. Selected Spectral Data for M(CO)sS(NR& No.
la
M
Cr
lb IC
NRz
2a
MO
3a
W
u(S-N),~
%rlaK (Log)b
6 ‘HNMRC
Free
Complex
N(CHs)z
945s
928s
392
2.98d
N 3
937s,915s
923s,sh;906s
392(3.22)
3.23((CH2)2)e,l.53((CH2)3)e
95Os,922s
930s,sh;920s
393(3.19)
3.53(OCH2)e,3.30(NCH2)e
N(CHzCaHs)z
940m
922m
395(3.4)
7.13(CeH,)d,4.13(CHz)d
Nz
95Os,922s
938s,sh;921s
398
3.50(OCH2)e,3.18(NCH2)e
95Os,922s
933s,918s
370(3.23)
3.56(OCH2)e,3.30(NCH2)e
Nb
Id
Complexes.
‘KBr, solid in cm-l. bn-hexane. Cppm from TMS in CCl4. Abbreviations: s: strong, m: medium, sh: shoulder.
of the complexes (Table III column 3) are similar to those of the free ligands but shifted downfield. For N-coordination two sets of signals, as those reported for the adducts with BH3 [4], should be expected. On the other hand the absorption maxima in UV-visible spectra (Table III column 2) observed at about 390 m~.1 for chromium and molybdenum, and at 370 ml.c for tungsten compounds, can be ascribed to the transition ‘A1 + ‘E that has been considered as characteristic for sulfur coordination in pentacarbonyl chromium and tungsten [ 121 compounds. In Table IV are reported the force constants kr and k2 for the C-O bonds calculated, according to the method of Cotton and Kreihanzel [ 111, from the stretching frequencies of the CO group reported in Table I. The k values obtained for the CO bonds in the thiobisamine complexes agree well with those reported for the same bonds in some Cr(CO)sL complexes in which L was a sulfur ligand [ 13-151. This fact is particularly significant in the case of kr which is very sensitive to the nature of the donor atom, specially to its capacity as a n-acceptor [ 131. The corresponding Graham 6 and rr parameters [ 161 are also reported in Table IV. According to the effects of the thiobisamine coordination on the CO bonds appearing from these data, the N,N’-thiobisamine are weak R-acceptor ligands. However, this is the kind of interaction that permits the formation of the complex in spite of the low nucleophilicity of the sulfur atom in the ligands. Among the complexes M(CO)sL (M = Cr, MO or W) with sulfur ligands reported at the time-with L= thioethers [ 171, thioamides and thioureas [ 18, 191, S(MR3)2 (M = Ge, Sn or Pb) [20], and SPRs [2 l] the thiobisamine complexes described here are the spectra
first metal-sulfur complexes with sulfur in a formal oxidation state +2. The main effects of the coordination to metal carbonyls on the properties of thiobisamine are a higher sensibility to electromagnetical radiation (Raman laser) and a greater susceptibility to hydrolysis. This latter effect is similar to that caused by the presence of acids or by the electrochemical oxidation of the thiobisamine to (R2N)sSt radicals [3], that also activate the heterolysis of the S-N bond.
Acknowledgements The authors thank Prof. E. Fluck, University of Stuttgart and Gmelin Institut Frankfurt, for facilities for performing a part of this work.
References 1 __O.E. Thompson, Q. Rep. Sulp. Chem., 5, 245 (1970). 2 G. Gonzilez, C. Diaz and S. Copaja, Monatsh. Chem., 114, 177 (1983). 3 G. Gonzkz, M. A. Santa Ana and I. Chadwick, J. Chem. Sot. Trans. Farad. II, in press. 4 H. Noth, G. Mikulascheck and W. Rambeck, Z. Anorg. Allg. Chem., 344, 316 (1966). 5 C. Romming, G. 0. Nevstad, J. Songstad, Acta Chem. Stand. A., 36, 399 (1982). 6 C. Diaz, E. Clavijo and G. Gonzilez,
Spectrochim.
Acta,
in press. 7 V. W. Hu, J. W. Gilje and T. T. Bopp, Inorg. Chem., 12, 955 (1973). 8 E. S. Blake,J. Am. Chem. Sot., 6.5, 1267 (1943). 9 M. Baudler and H. Mozaffar-Zanganeh, 2. Anorg. Chem., 423,203 (1976).
AZZg.
64 TABLE
C. Diaz and G. Gonzalez IV. Force Constantsa
Mo(CO)s
s
N (“) P
and Graham
2
WCO)s
aCalculated CReference
according
[ 131.
to the method dReference [ 141.
Parametersb
for C-O
Bonds in M(C0)sS(NR2)2
and other M(CO)sL
Complexes.
kl (md/A)
kz (md/A)
6
n
15.32
15.95
-0.12
0.05
15.29
15.97
0.19
0.01
15.31
15.97
0.10
0.09
15.36 15.44e 15.3oc 15.43e
15.99 15.9oe 15.91c 15.92’
0.13 -0.17 -0.01 -0.12
0.08 0.29 0.14 0.26
15.40
15.97
0.10
0.19
15.35e 15.41e 15.29= 15.38C
15.94e 15.99c 15.99e 15.88c
15.32
15.91
15.29d 15.37d 15.40c 15.28c 15.39c
15.86d 15.96d 15.89c 15.9oe 15.88C
of Cotton and Kreihanzel, eReference [ 161.
10 W. Strohmeier, Angew. Chem. Ed. Engl., 3, 730 (1964). 11 F. A. Cotton and C. S. Kraihanzel, J. Am. Chem. Sot., 84,4432 (1962). 12 E. W. Ainscough, F. J. Birch and A. M. Brodie, Inorg. Chim. Acta, 20, 187 (1976). 13 W. A. Schenk and M. Schmidt, 2. Anorg. Al/g. Chem., 416, 311 (1975). 14 R. A. Brown and G. R. Dobson, Inorg. Chim. Acta, 6, 65 (1972). 15 J. A. Connor and G. A. Hudson, J. Chem. Sot. Dalton 1025 (1975). 16 W. A. Graham, Znorg. Chem., 7, 315 (1968).
reference
-0.05e -0.1 0.02 -0.29
[ 111.
bCalculated
0.15e 0.22 0.10 0.30
0.16
0.02
0.01 0.13 -0.04 0.10 -0.05
0.12 0.10 0.20 0.07 0.20
according
to reference
[ 16 1.
17 H. Schumann, 0. Stelzer, R. Weis, R. Mohtachemi and R. Fischer, Chem. Ber., 106,48 (1973). 18 G. Gonzilez and J. Granifo, Znorg. Chim. Acta, 3.5, 209 (1979). 19 J. Granifo, J. Costamagna, A. Garrao and M. Pieber, J. Inorg. Nucl. Chem., 42, 1587 (1980). 20 W. Ehrl and H. Vahrenkamp, Chem. Ber., 103, 3563 (1970). 21 E. W. Ainscough, A. M. Brodie and A. R. Furness, J. Chem. Sot. Dalton, 2360 (1973). 22 C. Jeanne, R. Pince and R. Poilblanc, Spectrochim. Acta, 3IA, 819 (1975).